Fig. 4

Expansion and evolution analysis of GbNRTs in G. biloba. A Chromosomal location and collinearity analysis of GbNRTs genes in the genome of G. biloba. The background circle features gray lines representing colinear gene pairs within the Ginkgo genome. The yellow line signifies a colinear gene pair within the NPF family, while the blue line represents a colinear gene pair within the NRT2 family. The inner circle, denoted by blue and red boxes, illustrates the gene distribution density across chromosomes. The middle circle similarly indicates gene density through a polyline. Chromosome numbers are displayed outside the yellow circle. B Synteny analysis of NRTs between G. biloba and A. thaliana and P. trichocarpa. The background showcases gray lines denoting collinearity among different G. biloba and the two other species. Meanwhile, black lines symbolize paralogous NRT gene pairs